1. Technical Field
This invention relates to telephone stations and, more particularly, to telephone stations having directories for storing telephone numbers.
2. Description of the Prior Art
Telephone improvement programs in the last decade have resulted in a multitude of telephone station innovations which sere customer needs and facilitate ease of use. Illustratively, one such product is the caller-ID telephone station. When connected to a central office which provides caller-ID service, the caller-ID telephone station can read the telephone number of an incoming call and store this number in memory. With the caller-ID information, the called party may easily call back a calling party at a later time.
The incoming caller-ID information always includes the calling party's area code. If the calling party and called party are in the same area code, however, the area code information is usually not required for dialing the calling party. Thus, when the area code is not required to be dialed by the telephone station, it is deleted from memory while the telephone number is being stored in a list or directory of telephone numbers in the telephone station by the user.
In response to population growth/density pattern changes, boundaries between area codes are continually shifting. Thus a person living or working in a location covered by one area code today could find that same home or office being covered by another area code in the future. New area codes also are being created within old ones and, of course, people move from a location covered by one area code into another location covered by a different area code.
One consequence of these area code changes is that a user of a caller-ID telephone station, which maintains a directory of telephone numbers, will find, without warning, that many of the numbers for friends, relatives, and business associates stored in the directory of this telephone station to be unusable. If the user of the caller-ID telephone station moves or the station's locale is changed to a different area code, for example, those individuals who continue to be served by the original area code could not be called from the caller-ID based directory because the area code information for these numbers was previously not needed and therefore deleted when the caller-ID information was stored in the directory in the caller-ID telephone station. As a result, the caller-ID telephone station will not contain the area code for telephone numbers that it needs and also contain the area code for telephone numbers that it no longer needs. Thus, with each telephone number affected by an area code change, the user must manually reprogram the directory by either including the area code or deleting the area code for each affected telephone number in the directory as appropriate.